musb_hdrc: fix some bugs in the updated host side code

 - Remove an oops in the queue fault cleanup path, caused by using the
   wrong giveback routine (heavy weight vs lighter-weight).  Move a few
   key bits of code into that lighter weight version.

 - Trigger that lighter-weight cleanup during URB completion, when the
   URB in question can't yet been handed off to the hardware even if
   it's at the queue head.

 - Reduce syslog noise when those fault cleanup paths are triggered from
   scatterlist calls by usb-storage.

 - Paranoia: when scheduling, insist that the endpoint fifo isn't smaller
   than required.

Oops observed courtesy of a slightly flakey usb-storage device, which
once again proves itself handy for testing.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index c175db4be2b27ad78e92f90daf7cbd52d096d86f..669e15e69445f6b5d624bf51896701d56fa08236 100644 (file)
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -243,14 +243,12 @@ start:
        }
 }
 
-/* caller owns no controller locks, irqs are blocked */
-static inline void
-__musb_giveback(struct musb_hw_ep *hw_ep, struct urb *urb, int status)
-__releases(urb->lock)
-__acquires(urb->lock)
+/* caller owns controller lock, irqs are blocked */
+static void
+__musb_giveback(struct musb *musb, struct urb *urb, int status)
+__releases(musb->Lock)
+__acquires(musb->Lock)
 {
-       struct musb     *musb = hw_ep->musb;
-
        if ((urb->transfer_flags & URB_SHORT_NOT_OK)
                        && (urb->actual_length < urb->transfer_buffer_length)
                        && status == 0
@@ -270,6 +268,7 @@ __acquires(urb->lock)
                                /* common/boring faults */
                                case -EREMOTEIO:
                                case -ESHUTDOWN:
+                               case -ECONNRESET:
                                case -EPIPE:
                                        level = 3;
                                        break;
@@ -285,7 +284,9 @@ __acquires(urb->lock)
                        urb->actual_length, urb->transfer_buffer_length
                        );
 
+       spin_unlock(&musb->Lock);
        usb_hcd_giveback_urb(musb_to_hcd(musb), urb, musb->int_regs);
+       spin_lock(&musb->Lock);
 }
 
 /* for bulk/interrupt endpoints only */
@@ -323,8 +324,6 @@ static inline void musb_save_toggle(struct musb_hw_ep *ep, int is_in, struct urb
 /* caller owns controller lock, irqs are blocked */
 static struct musb_qh *
 musb_giveback(struct musb_qh *qh, struct urb *urb, int status)
-__releases(qh->hw_ep->musb->Lock)
-__acquires(qh->hw_ep->musb->Lock)
 {
        int                     is_in;
        struct musb_hw_ep       *ep = qh->hw_ep;
@@ -349,9 +348,7 @@ __acquires(qh->hw_ep->musb->Lock)
        }
 
        qh->is_ready = 0;
-       spin_unlock(&musb->Lock);
-       __musb_giveback(ep, urb, status);
-       spin_lock(&musb->Lock);
+       __musb_giveback(musb, urb, status);
        qh->is_ready = ready;
 
        /* reclaim resources (and bandwidth) ASAP; deschedule it, and
@@ -1744,7 +1741,7 @@ static int musb_schedule(
                else
                        diff = hw_ep->wMaxPacketSizeTx - qh->maxpacket;
 
-               if (wBestDiff > diff) {
+               if (diff > 0 && wBestDiff > diff) {
                        wBestDiff = diff;
                        nBestEnd = nEnd;
                }
@@ -2018,7 +2015,7 @@ static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
         * has already been updated.  This is a synchronous abort; it'd be
         * OK to hold off until after some IRQ, though.
         */
-       if (urb->urb_list.prev != &qh->hep->urb_list)
+       if (!qh->is_ready || urb->urb_list.prev != &qh->hep->urb_list)
                status = -EINPROGRESS;
        else {
                switch (qh->type) {
@@ -2043,8 +2040,12 @@ static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
 
        /* NOTE:  qh is invalid unless !list_empty(&hep->urb_list) */
        if (status < 0 || (sched && qh != first_qh(sched))) {
-               status = -EINPROGRESS;
-               musb_giveback(qh, urb, 0);
+               int     ready = qh->is_ready;
+
+               status = 0;
+               qh->is_ready = 0;
+               __musb_giveback(musb, urb, 0);
+               qh->is_ready = ready;
        } else
                status = musb_cleanup_urb(urb, qh, urb->pipe & USB_DIR_IN);
 done: